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Figure 140. Enhanced Transmission Selection
The following table lists the traffic groupings ETS uses to select multiprotocol traffic for transmission.
Table 121. ETS Traffic Groupings
Traffic Groupings Description
Priority group A group of 802.1p priorities used for bandwidth allocation and
queue scheduling. All 802.1p priority traffic in a group must
have the same traffic handling requirements for latency and
frame loss.
Group ID A 4-bit identifier assigned to each priority group. The range is
from 0 to 7.
Group bandwidth Percentage of available bandwidth allocated to a priority
group.
Group transmission selection algorithm (TSA) Type of queue scheduling a priority group uses.
In the Dell Networking OS, ETS is implemented as follows:
● ETS supports groups of 802.1p priorities that have:
○ PFC enabled or disabled
○ No bandwidth limit or no ETS processing
● Bandwidth allocated by the ETS algorithm is made available after strict-priority groups are serviced. If a priority group does
not use its allocated bandwidth, the unused bandwidth is made available to other priority groups.
● For ETS traffic selection, an algorithm is applied to priority groups using:
○ Strict priority shaping
○ ETS shaping
● ETS uses the DCB MIB IEEE 802.1azd2.5.
Configuring DCB Maps and its Attributes
This topic contains the following sections that describe how to configure a DCB map, apply the configured DCB map to a port,
configure PFC without a DCB map, and configure lossless queues.
DCB Map: Configuration Procedure
A DCB map consists of PFC and ETS parameters. By default, PFC is not enabled on any 802.1p priority and ETS allocates equal
bandwidth to each priority. To configure user-defined PFC and ETS settings, you must create a DCB map.
1. Enter global configuration mode to create a DCB map or edit PFC and ETS settings.
CONFIGURATION mode
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FC Flex IO Modules